curl --request GET \
  --url https://api.paygentic.io/v2/invoices/{id}/lineItems \
  --header 'Authorization: Bearer <token>'

{
  "invoiceId": "inv_r1s2t3u4v5w6x7y8",
  "lineItems": [
    {
      "eventType": "usage",
      "eventId": "usg_a1b2c3d4e5f6g7h8",
      "eventSourceId": "bm_l5m6n7o8p9q0r1s2",
      "invoiceDisplayName": "Claude Token Consumption",
      "lineItemType": "charge",
      "meterEventId": "me_x9y0z1a2b3c4d5e6",
      "metricDescription": "Language model token consumption",
      "metricName": "Token Usage",
      "metricUnit": "tokens",
      "quantity": 2500,
      "taxRate": 0.085,
      "totalAmount": "0.05425",
      "totalPrice": "0.05",
      "totalTax": "0.00425",
      "unitPrice": "0.00002"
    },
    {
      "eventType": "fee",
      "eventId": "fee_b2c3d4e5f6g7h8i9",
      "eventSourceId": "fee_h3i4j5k6l7m8n9o0",
      "invoiceDisplayName": "Platform Fee",
      "meterEventId": "",
      "metricDescription": "Monthly platform fee",
      "metricName": "Platform Fee",
      "metricUnit": "charge",
      "quantity": 1,
      "taxRate": 0.1,
      "totalAmount": "5.50",
      "totalPrice": "5.00",
      "totalTax": "0.50",
      "unitPrice": "5.00"
    }
  ],
  "nextPageToken": null,
  "totalCount": 3
}